Copper, PVC, or PEX? Understanding the Pipes in Your Home

Ask most homeowners what kind of pipe carries water through their walls and you'll get a shrug. That's understandable; it's not something you think about until there's a leak or a renovation forces the question. Knowing the basics, though, helps you understand what you're dealing with, what its typical lifespan looks like, and roughly what era your home's plumbing was likely installed in.

Copper

Copper has been a standard choice for water supply lines for decades, prized for its durability and natural resistance to bacteria. It handles both hot and cold water well and has a long track record, often lasting 50 years or more when properly installed and maintained.

The downsides are cost and installation complexity. Copper is more expensive than plastic alternatives, and joining sections requires soldering (or newer press-fit tools), which takes more skill than gluing or crimping plastic pipe. Copper can also be susceptible to corrosion in areas with highly acidic water, sometimes developing pinhole leaks over time in those conditions.

PVC (and CPVC)

PVC (polyvinyl chloride) is a rigid plastic pipe most commonly used for drain, waste, and vent lines rather than pressurized water supply, since standard PVC isn't rated for hot water. A close relative, CPVC (chlorinated polyvinyl chloride), is specifically designed to handle hot water and is sometimes used for supply lines, though it's become less common as PEX has grown in popularity.

PVC is inexpensive, resistant to corrosion, and relatively easy to work with, using solvent cement to join sections rather than soldering. It's a common sight in basements and crawlspaces for drain lines in homes of almost any age built or replumbed from roughly the 1970s onward.

PEX

PEX (cross-linked polyethylene) is a flexible plastic tubing that has become the dominant choice for new water supply lines in residential construction over the past couple of decades. Its flexibility is a major advantage. It can snake through walls and around obstacles with far fewer joints and fittings than rigid pipe, which means fewer potential leak points. It's also more resistant to freeze damage than copper, since it can expand slightly rather than always cracking under the pressure of freezing water.

PEX is generally less expensive to install than copper and is often the material of choice for repiping an older home, precisely because of how much easier it is to route through existing walls without extensive demolition.

What your home's age likely tells you

• Homes built before the 1960s: may still have original galvanized steel supply pipes, which are prone to internal corrosion and reduced water pressure over time as the interior diameter narrows with rust buildup.
• Homes from the 1960s through the 1990s: commonly have copper supply lines, often still in good condition if well maintained.
• Homes built or replumbed from the 2000s onward: increasingly likely to have PEX supply lines, often alongside PVC for drain and vent lines.

These are general patterns, not guarantees. Many homes have a mix of materials from different renovations over the years, and the only way to know for certain what's behind your walls is a direct inspection.

Why this matters for you

Understanding your home's likely pipe material helps you anticipate what kind of issues to watch for, whether that's corrosion in older copper, pinhole leaks in acidic-water areas, or brittleness in aging PVC. If you're planning a renovation, dealing with recurring leaks, or just curious what's actually running through your walls, ProFlow Plumbing can identify your home's specific plumbing materials and flag anything that's approaching the end of its useful life.